The invention relates to a grounding pin for connecting a vehicle body to a pole of a vehicle battery, a grounding pin connection with such a grounding pin, and a motor vehicle with such a grounding pin or grounding pin connection.
FIG. 1 shows a known grounding pin 1 for connecting a vehicle body to a minus pole of a vehicle battery. The grounding pin 1 has a pin plate 2 from which a pin shaft 3 protrudes, the pin shaft being provided with an external thread. A cable lug of a line leading to the vehicle battery can be fastened to the grounding pin 1. More precisely, the cable lug is mounted on the grounding pin 1 such that the pin shaft 3 extends through the opening of the cable lug and is then screwed tight by means of a nut on the pin shaft 3 on the grounding pin 1. One end of the cable lug opposite the line is provided with an angle section, which encloses the pin plate 2 so that the cable lug can only be oriented in one of the four predetermined positions, each set off from the others by 90°. When attaching the grounding line one must pay attention that a particular orientation of the cable lug is required, or else the cable guidance of the grounding line is not optimal or not possible as intended. This particular orientation may vary according to the vehicle model. Due to the variable orientation possibility, however, a wrong orientation or wrong installation is possible, which might then become evident during the laying of the line, for example, but unnecessary work time is squandered.
One problem which the present invention proposes to solve is to provide a grounding pin for connecting a vehicle body to a pole of a vehicle battery, which heightens the installation safety.
According to one exemplary embodiment of the invention, a grounding pin is provided for connecting a vehicle body to a pole of a vehicle battery, comprising a pin plate and a pin shaft which protrudes from the pin plate and is provided with an external thread and the longitudinal axis of which forms a center line of the grounding pin, wherein the pin plate has a single or two installation securing faces which point radially outward and which are each parallel to a face which passes through the center line, wherein a minimum distance between a circumferential face of the pin plate and the center line lies in the range of the installation securing face/faces, and wherein the pin plate is provided with a connection face which points away from the pin shaft and is matched to the vehicle body for welding purposes. Because the installation securing face creates a region forming the circumferential region with the smallest distance in relation to the overall circumferential face, a cable lug can only be mounted in a predefined orientation on the grounding pin, which creates installation safety.
According to a further exemplary embodiment of the invention, the circumferential face of the pin plate is round outside of the installation securing face/faces.
According to a further exemplary embodiment of the invention, contact wedge elements are provided around the pin shaft, each of them having an edge which starts at the radially outward pointing face of the pin shaft and extends at a slant away from the pin shaft and toward the pin plate. Thanks to these contact wedge elements, the junction resistance between the cable lug and the grounding pin is decreased.
According to a further exemplary embodiment of the invention, the pin plate on the side facing toward the pin shaft has two parallel faces, of which an outer face surrounds an inner face as a ring and the inner face is situated closer to the pin shaft along the center line than the outer face.
According to a further exemplary embodiment of the invention, the pin shaft is provided with an external thread, especially an M8 thread or larger. It has been found that a thread of size M8 is best suited for the function of a grounding pin in motor vehicles.
According to a further exemplary embodiment of the invention, the connection face is provided with welding elevations, especially welding elevations that are suitable for a hump welding.
According to a further exemplary embodiment of the invention, the installation securing face extends in a straight line and entirely through the pin plate. This installation securing face extending entirely through the pin plate is easy and thus cost-effective to produce.
According to a further exemplary embodiment of the invention, the installation securing face is the surface of a groove, so that on either side of the installation securing face there are situated side flanks of the groove.
Furthermore, the present invention provides a grounding pin connection with a grounding pin according to one of the preceding exemplary embodiments and a cable lug, which can be fastened on one end of a cable and has an angle section at its end opposite the cable, which lies against the installation securing face.
Moreover, the present invention provides a motor vehicle with such a grounding pin or such a grounding pin connection.
In the following, a preferred exemplary embodiment of the present invention shall be described, making reference to the accompanying drawings.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.